Assessment of Physicochemical Properties and Heavy Metal Content of Floriculture Soil in Amhara Region of Northwest Ethiopia

Floriculture is a new and rapidly expanding sector in Ethiopia that aids economic growth but has also come under blame for pollution of the surrounding soil. The purpose of this study was to assess the soil physicochemical properties and heavy metal contents in floriculture in the Amhara Region of Northwest Ethiopia. Soil samples were collected from seven different greenhouses (2ABC, 4DEF, 5ABC, 7DEF, 8ABC, 9DEF, and 11DEF), and a control soil sample was taken on the 15-cm depth from a nearby agricultural area. They were analyzed for soil physicochemical parameters and heavy metal compositions. Soil texture showed a significant difference between the soils sampled from the greenhouses and the control group. The highest average clay, silt, and sand contents were recorded in the control group, 4DEF, and 9DEF, respectively. The lower clay content was at 9 DEF, silt at 11 DEF, and sand in the control group. Clay was positively correlated to soil pH (r = 0.66) and TN (r = 0.38) but showed significant negative correlation with the sand fraction (r = −0.96). The average bulk density (BD) values of the soils from the greenhouses were within acceptable ranges; however, the mean BD value of 7DEF was relatively highest (1.34 g/cm3). There were significant (P < 0.05) changes in soil pH and electrical conductivity, with pH values ranging from 5.8 to 7.17 and EC from 0.08 to 1.72 mScm−1. Soil organic carbon, available phosphorus, total nitrogen, and carbon-to-nitrogen ratio of the soil samples from the greenhouses and the control group were significantly different. There were also significant differences in soil exchangeable aluminum and acidity between greenhouse soil samples and the control group. Soil contents of some of the heavy metals (Pb, Cd, Mn, and Cu) in the floriculture soil were above the permissible limits, while Cr, Zn, and Ni contents were below. The soil in floriculture showed low quality compared to the control group and international standards, indicating the need for improved soil quality management. This study recommends reducing agrochemical use, increasing bio-fertilizers, using botanicals, and transitioning to organic farming. Further studies are needed to assess soil microbial diversity and abundance for soil fixation.


Introduction
Floriculture is a segment of horticulture and is concerned with the cultivation of fowering and ornamental plants [1], commercializing bedding plants, cutting fowers, potted fowering plants, and noncommercial home gardening [2].It has reached a historical maximum hub of activity and competitiveness due to the continuous development of greenhouse technology, advances in plant biotechnology, and marketability [3,4].In Ethiopia, foriculture is young (it began in the mid-1990s), the fast-growing industry that has grown to become the world's fourth largest fower exporter and Africa's second largest, employing over a hundred thousand people and generating foreign currency [2,5].
Despite the foriculture industry contributes signifcantly to the national economy through the export of cut fowers and the creation of jobs [1,6], it is blamed for polluting the environment and posing health risks [2].Agrochemical residues, such as heavy metals and organic compounds, can destroy benefcial organisms in the soil [7], and it is well recognized that soil contamination can lead to water pollution if toxic chemicals leak into groundwater or contaminated runof reaches streams, lakes, or seas [8,9].For instance, heavy metal inputs and contaminants such as cadmium (Cd) and lead (Pb) from phosphorus and superphosphate fertilizers can cause serious problems in water [10] and have the potential to harm nitrogen-fxing bacteria and other soil microbes [11].Soil pollution as part of land degradation is caused by the presence of xenobiotic chemicals or other alterations in the natural soil environment [3,12].
Heavy metals and metalloids from leaded gasoline and paints, fertilizer application on land, animal manures, sewage sludge, pesticides, coal combustion residues, and petrochemical leakage are all possible sources of pollution [13].Heavy metals constitute of inorganic chemical hazards, and those most commonly found at contaminated sites are lead (Pb), chromium (Cr), arsenic (As), zinc (Zn), cadmium (Cd), copper (Cu), mercury (Hg), manganese (Mn), and nickel (Ni) [14].Heavy metals are well-known environmental pollutants due to their toxicity, environmental persistence, and bioaccumulative nature [15].Despite the limited studies conducted across counties, the practice, chemical types and usage, and dosages can vary depending on the environment, competence, and foriculture expertise and worker knowledge.Terefore, the present study aimed to evaluate the status of heavy metal contents and physicochemical properties of foriculture soil, Amhara region, Northwest Ethiopia.

Objectives of the Study
1.1.1.General Objective.Te general objective of this study was to assess the physicochemical properties and heavy metal content of foriculture soil in the Amhara Region of Northwest Ethiopia.

Specifc Objectives: Te Specifc Objectives Were
(i) To assess foriculture soil physicochemical properties (ii) To determine the heavy metal pollution potential of foriculture soil

Description of the Study Area.
Te study was conducted in TAL foriculture, Bahir Dar Zuria district, Northwestern Ethiopia, 565 km northwest of Addis Ababa and 11.3 km from the regional capital city as described in Figure 1.

Climate of the Study Area.
Te study area, based on 1985-2020 meteorological data, has a unimodal rainfall pattern with an average annual rainfall of 79.41 mm and a warm climatic condition with annual mean minimum and maximum temperatures of 11.37 °C and 27.31 °C, respectively, as described in Figure 2.

Sampling Procedure and Sample Size Determination.
In this study, soil samples were taken from seven randomly selected greenhouses (namely, 2ABC, 4DEF, 5ABC, 7DEF, 8ABC, 9DEF, and 11DEF) from a total of 14 TAL foriculture greenhouses and one soil sample from the nearby agricultural feld as a control group, and thus, a total of eight soil sample sites were used for the study to assess the soil physicochemical properties and heavy metal contents.Te soil samples were collected in triplicate in each of the TAL foriculture greenhouses each of them treated with unique chemical (Fe, Cu, Mg, Ca, Map, T vag, and Bilanka menda Chinese, respectively, to each of the greenhouse) and the control soil sample using soil sampler Auger.Eight soil sample pits were utilized in each greenhouse to collect samples from a depth of 0-15 cm, the sample was bulked and mixed after roots and debris were removed, and three composite samples per greenhouse were bagged and tagged in polyethylene bag for laboratory analysis.After that, the composite soil samples were air-dried, crushed, and sieved at 2 mm mesh.Furthermore, undisturbed soil samples of known volume were obtained with a sharp-edged steel cylinder (soil sample corer) forced manually for the soil bulk density determination.Moreover, the following soil property parameters were analyzed in the soil laboratory: soil texture, bulk density, soil pH (H 2 O), soil electrical conductivity (SEC), soil organic carbon (SOC), soil organic matter (SOM), total nitrogen (TN), available phosphorous (Ava P), C : N ratio, exchangeable Aluminum, exchangeable acidity, and hydrogen.GPS was used to identify the geographical locations of the soil sampling sites.Tis investigation is crucial for understanding soil quality and fower production rates.

Data Analysis.
Te data in soil physicochemical properties and heavy metal contents among TAL foriculture greenhouses and the control groups were subjected to a one-way analysis of variance (One-Way ANOVA) using SPSS Version 20, at P < 0.05 signifcant levels.Mean comparisons were employed using least signifcant diference (LSD) test at 5% levels, to assess variations in the soil physicochemical properties and heavy metal contents among foriculture greenhouses.Descriptive statistics (mean, standard error) were also used to analyze the relationship between soil property variables and interpret relevant data sources.Pearson correlation matrix analysis was done using corrplot Rpackage (R Core Team, V.4.1.3,2022).

Soil Sample Laboratory Analysis
2.3.1.Soil Physical Properties.Soil textural analysis (particle size) was analyzed following the hydrometer method after destroying OM using hydrogen peroxide and dispersion in a mixer with sodium hexametaphosphate (NaPO 3 ) 6 [16].Bulk density was determined using the undisturbed core sampler method using a volumetric cylinder and calculated by dividing the oven-dry mass at 105 °C by the volume of the core [16].
2 Te Scientifc World Journal 2.3.2.Soil Chemical Properties.Te pH of the soil was measured in water (pH (H 2 O)) potentiometrically using a digital pH meter in the supernatant suspension of 1 : 2.5 soils to water ratio using a glass-calomel combination electrode [17].Soil electrical conductivity was determined using the standard method [18].Total nitrogen (TN) content was measured using the Kjeldahl digestion, distillation, and titration method [17].Soil organic carbon content was analyzed by wet combustion methods [19].Soil organic matter was determined by using titrimetric methods, and then its contents were estimated from the organic carbon content by multiplying by 1.724.Te soil's available phosphorous content was determined by measuring absorbance on a spectrophotometer following the method of extraction according to Bray II [20].Te exchangeable acidity was determined by percolating the soil samples with 1 M KCl solution and titrating them with 0.02 M NaOH.From the same extract, exchangeable Al 3+ in the soil samples was titrated with a standard solution of 0.02 M HCl.Ten, the exchangeable H + was obtained by subtracting exchangeable Al 3+ from exchangeable acidity, which is Al and H ions [21].
One gram of soil sample was weighed and transferred to  Te Scientifc World Journal a digestion vessel.Ten, sixteen milliliters per chloric acid and four-milliliter hydrogen peroxide (4 : 1 ratio) was added to the Kjeldahl digester tube and heated at 180 °C for three hours.Finally, the heavy metal contents (Pb, Cr, Cd, Cu, Zn, Ni, and Mn) were determined using the ICP-OES multielement analysis method [22].

Results and Discussion
3.1.Soil Physical Properties of TAL Floriculture.Te soil samples collected from foriculture greenhouses and the control group soil sample in this investigation revealed a substantial (P < 0.05) variation in clay concentration.Te results of the post-hoc analysis revealed that the soil samples used as a control group had the greatest average clay content (55.67 ± 1.20), followed by soil samples at 2ABC (51.0 ± 0.57), while 9DEF had the lowest average value (3.67 ± 0.88) Yihune et al. [23].Tis considerable decrease in the percentage of clay in the greenhouses as compared to the control group may be related to the human disturbances that might alter parent material, such as continuous farming for fower production and extended chemical application.According to Gupta [24] and Dastgheyb Shirazi et al. [25], soil texture is an inherent soil property that may have contributed indirectly to the changes in particle size distribution.Also, there was a considerable diference in sand and silt fractions among the soil samples from the greenhouses and the control group.Te highest (27.0 ± 0.57) and lowest (11.0 ± 1) values of the silt fraction were reported at the 4DEF and 11DEF greenhouses, respectively, Table 1, notwithstanding the notable fuctuation.
On the other hand, the control groups had the lowest sand fraction (24.3 ± 1.20) and the greenhouse sites had the highest (9DEF, 70.3 ± 1.45).Te greenhouse site 9DEFs observed sand soil content might be the result of intensive agricultural practices that expose the soil to excessive water fow and cause fne particles like clay to be lost.Tis fnding agreed with the work of Gebeyaw [26], who stated that intensive farming causes soil compaction and degradation of soil properties including porosity.Te result also showed that the soil textural classes of the study areas were sandy loam, clay loam, silt clay loam, and sand clay loam.Similar research fndings revealed that continuous application of chemicals for foriculture afects the nature of the parent materials and increases the proportion of the sand fraction of the soil [27].Sandy soils were poor for fower farming, more water to be freely drainage and unavailable for cultivation fower farming use.As shown in Figure 3, clay had a negative and substantial association with sand (r = −0.96)and a positive correlation (r = 0.66) with the other soil physicochemical characteristics, such as pH and total nitrogen (TN).Tis indicated that, compared to sand and other negatively correlated features, soil clay concentration greatly raised soil pH and total nitrogen content in the soil system, with the impact being more pronounced in the control group than in the foriculture soils.
According to FAO [28], bulk density (BD) values typically range between 0.8 and 2.0 gm/cm 3 .In this study, BD showed a statistically signifcant diference (P < 0.05) between the soils in the greenhouses of the foriculture soil and the control group as described.Even though the soils in the investigated greenhouses and control group are within an acceptable range and ideal for plant growth, the greater (1.34 gm•cm −3 ) and lower (1.03 gm•cm −3 ) BD values in the greenhouses soil were obtained in 7DEF and 4DEF, respectively, as described in Table 1.Te possible reason for the diference is attributed to the continuous tillage during farming activities in the greenhouse.Tis result is in arrangement with the research fndings reported by [29].Similarly, the low bulk density values for the soils in the foriculture greenhouses could be the result of the addition of compost and manure for foral production, which increases soil porosity and water holding capacity, in turn, reducing BD Yerima and Van Ranst [30].

Soil pH, Exchangeable Acidity, and Electrical
Conductivity.Te results of the analysis of variance showed that there was a substantial (P < 0.05) variation in soil pH (H2O) between the soils in the control group and the analyzed foriculture greenhouses.Table 2 soil sample pH for the 9DEF greenhouse was 5.8 ± 0.09, but it was higher (7.17 ± 0.03) in the control group, according to the post-hoc test.Te lowest pH value observed in the greenhouse 9DEF may be attributed to ongoing application of fertilizer, pesticides, and herbicides, removal of basic cations by harvested fowers, increased microbial oxidation producing organic acids that lower soil pH by adding H ions to the soil solution.Tese results are in agreement with Ogumba et al. [31].According to FAO [32], the pH of all soil samples was within the recommended range (5.5 to 7) for the availability of most essential nutrients to plant growth and development as described in Table 2, and thus, the risk of pollution in the area in terms of soil pH was low.Long-term use of pesticides and inappropriate fertilizers, such as di-ammonium phosphate (DAP) (NH 4 ) 2 HPO 4 , in the soil for foral production, however, may cause toxicity and/or acidity in the soil constituents.According to the research fndings, the use of certain pesticides, notably for fower production, has been proven to toxoid the soils in foriculture in Ethiopia [33].
Te assessment of soil exchangeable acidity is a useful indicator of its reserve or potential acidity, particularly in the foriculture business, which uses a lot of chemicals that are thought to cause soil toxicity [1].Te investigated soils in foriculture greenhouses difered signifcantly (P < 0.05) in exchangeable acidity from the control group in this study.Table 2 shows that the exchangeable acidity ranged from 2.83 to 4.16 cmol + •kg −1 , with the greatest average value found in 2ABC greenhouses and the lowest in 9DEF greenhouses.Tis might be explained by the fact that regular applications of insecticides, herbicides, and inorganic fertilizers in the greenhouse leave behind acidic cations.On the other hand, the buildup of organic matter from the fower litters' leaves may be the cause of the low rate of acidity under the greenhouse of TAL foriculture.Tis was in line with the fndings of [2]. 4 Te Scientifc World Journal Furthermore, Table 2 indicates a statistically signifcant (P < 0.05) variation in electrical conductivity between the soils in the greenhouse and the control group.Despite this diference, Table 2 shows that the soil EC values in the soil samples collected in the 8ABC greenhouse and the control group were the highest (1.72 ± 0.001 ms•cm −1 ) and lowest (0.08 ± 0.00 ms•cm −1 ), respectively.Te continuous application of certain base-forming chemicals through fertilizer and pesticides may be the cause of the highest EC values under the 8ABC greenhouse soil.Consequently, some of the  essential nutrients needed in large quantities for plant growth and development, like soil organic matter, total nitrogen, and available phosphorous, are also enhanced in the defned greenhouse soils which is similar with the fnding of Obalum et al. [34].Te EC value shows the number of soluble salts in an extract and therefore provides an indicator of soil salinity.Low values of electrical conductivity obtain show that the soils are suitable for fower farming.[35] It is reported that soil with EC values less than 1 ms•cm −1 is suitable for plant growth.

Soil Organic Carbon, Available Phosphorous, and Total
Nitrogen.Soil organic carbon, available phosphorus, and total nitrogen are the most important factors in terms of soil fertility and healthy, plant growth, crop production, soil microbial diversity, and function [36].According to the results of the analysis of variance, there was a substantial (P < 0.05) variation in soil organic carbon between the soils of foriculture greenhouse and the control groups.
According to Figure 4, the post-hoc test revealed that the soil organic carbon in greenhouse 2ABC was higher (3.4 ± 0.02) than in greenhouse 4DEF greenhouse soil (2.34 ± 0.02), the latter being a foriculture greenhouse.Te removal of harvested fowers, ongoing use of pesticides, fertilizers, herbicides, or agrochemicals, as well as microbial oxidation that generates organic acids and decreases soil organic carbon levels, might all be contributing factors to the reduced levels of organic carbon Obalum et al. [37].Organic carbon showed a positive correlation (r � 0.33) with clay, a negative correlation (r � 0.48) with available phosphorous, and a negative correlation (r � 0.48) with sand.However, TN in the analysis of variance showed that the soils in the foriculture greenhouse and the control groups are difered substantially (P0.05).According to Figure 4, the post-hoc test revealed that soil TN was lower (0.05 ± 0.01) in the soil of the 11DEF foriculture greenhouse than it was in the control group (0.32 ± 0.05).Te result of this study TN of soils under the greenhouse of foriculture soil can be described as a low rate as similar with the fnding of Tyopine et al. [38].Tese low values of total nitrogen the area is moist that causing leaching of nitrogen despite fertilizer additions and might be related to low input of nitrogen reach organic materials such as manure, compost and unable to integrate leguminous plants on fower farm soil that fx nitrogen.Te low nitrogen content likewise [39] reported that total nitrogen contents were lower in continuously farming of foriculture and use of agrochemicals.
Te soil available phosphorus in the control group and foriculture greenhouse soils difered considerably (P < 0.05) from each other, according to the analysis of variance.According to Figure 4, the soil available phosphorus was decreased (1.12 ± 0.13) in the soil of the 7DEF foriculture greenhouse, while it was higher (3.5 ± 0.04) in the control group.Tis was revealed by the post-hoc test.According to Barber [40], the available phosphorus content less than 5 mg•kg −1 is rated low.Consequently, it was discovered that the soils of foriculture greenhouses had a low rate of available phosphorus.Te nature of the parent material from which the soils are produced, the extraction of more phosphorus by fower plantations, and the leaching and fxing of iron and aluminum, which are abundant in contaminated soils, might all be the reasons for the lower reported available phosphorus content in foriculture soil that is congruent with the fnding of [41].

Soil Organic Matter and Carbon-Nitrogen Ratio (C : N).
Soil OM and C : N have an important infuence on soil's physical and chemical characteristics, soil fertility status, plant nutrition, and biological activities in the soil [29].Te analysis of variance revealed that soil OM was signifcantly (P < 0.05) diferent among the soils in the foriculture greenhouse and the control groups.Te post-hoc test showed that soil OM was greater (4.0 ± 0.38%) in the 5ABC greenhouse but lower (4.0 ± 0.38%) in the soil of the 4DEF foriculture greenhouse as described in Figure 5. Tis result is in agreement with [42].
Te soil carbon-nitrogen ratio (C : N) in the foriculture greenhouse and control groups difered considerably (P < 0.05) according to the results of the analysis of variance (ANOVA).According to Figure 5, the post-hoc test revealed that the soil C : N ratio was higher (19.4 ± 2.7) in the 9DEF greenhouse but lower (10.5 ± 2) in the 2ABC foriculture greenhouse.A similar study by [43] states that high C : N ratios therefore suggest that the OM contents were not well mineralized (immobilizations were strongly preferred).High soil C : N ratios can limit soil microbial activity and reduce nitrogen mobilization, which can slow down the pace at which organic matter and nitrogen break down.On the other hand, a low soil C : N ratio may hasten the microbial breakdown of nitrogen and organic materials.Tis study is congruent to the fndings of Ogumba et al. [31].According to Figure 3, when OM was connected with various soil physicochemical characteristics, it was negatively correlated with sand (r � 0.27), silt (r � 0.34), EC (0.48), and clay (r � 0.33), pH (r � 0.5), available phosphorous (r � 0.4), and TN (r � 0.48).Tis indicated that the amount of clay in the soil raises the amount of total nitrogen and soil organic carbon in the soil system more than sand does and that these two attributes are negatively correlated.Te result was more pronounced in the control group than in the soils used for foriculture.

Heavy Metal Contents of Floriculture.
In the present study, the heavy metal content showed a signifcant (P < 0.05) diference between the soils sampled in foriculture greenhouses and the control group.Te post-hoc test showed the highest average chromium (Cr) content was recorded under greenhouse 9 DEF (51.35 ± 0.09 mgkg −1 ) followed by greenhouse 7DEF (47.20 ± 0.03 mgkg −1 ), whereas the lower average value of Cr (22.13 ± 0.12 mgkg −1 ) was recorded in the control group as described in Table 3.In all collected foriculture soil samples, the concentration of Cr was recorded below the permissible limit set by CCME (100 mg•kg −1 ).Tis signifcant increment of Cr in the greenhouses compared to the control group could be associated with the result of anthropogenic activities, such as prolonged application of agro-chemicals like fertilizer, 6 Te Scientifc World Journal herbicides, and pesticide chemicals.Excess chromium in the soil has an unfavorable or toxic efect on plants, animals, and humans.Te oxyanion chromate Cro 4 2-is highly mobile and more toxic in soils [44].
In the present study, lead content showed a signifcant (P < 0.05) diference between the soils sampled in foriculture greenhouses and the control group as described.Te mean total concentration of lead in the foriculture soil samples was highest in the 2ABC (9.80 ± 0.10 mg•kg −1 ) greenhouse, followed by 4DEF (9.62 ± 0.21 mg•kg −1 ), whereas the lowest average lead content was recorded in the control group (7.32 ± 0.02 mg•kg 1 ).In all collected foriculture soil samples, the concentration of lead was recorded above the permissible limit set by CCME (0.66 mg•kg −1 ).Tis might be due to the prolonged application of agrochemicals.
According to research fndings, lead is a common heavy metal pollutant that must have a negative impact on soil health in order to afect plant development [14].In terms of correlation with other soil heavy metal contents, Cr was positively correlated with cadmium (r � 0.55), manganese (r � 0.41), and copper (r � 0.90) but negatively correlated with zinc (r � −0.39) (Figure 6).
Te analysis of variance revealed that soil Cd content was signifcantly (P < 0.05) varied among soils in the TAL foriculture greenhouse as described.Te post-hoc test showed that soil Cd content was higher (10.55 ± 0.03 mg•kg −1 ) in the greenhouse 5ABC but lower (5.82 ± 0.03 mg•kg −1 ) in the soil of the control group.In all the collected foriculture, soil sample concentrations of cadmium were recorded above the maximum permissible limit of CCME (1.4 mg•kg −1 ).Terefore, the high Cd value may have resulted from the Mean values within the same letters are not signifcantly diferent (P < 0.05), * signifcant at (P < 0.01).
Te Scientifc World Journal frequent use of fertilizers for foriculture activities, which are the sources of Cd in the soil.Te present study is in agreement with the fndings of Mico Llopis et al. [45], who stated that heavy metal contaminants afect the agricultural soils.Te analysis of variance revealed that foriculture soil Zn content was signifcantly (P < 0.05) varied among the soils in the foriculture soil greenhouse.Te post-hoc test showed that foriculture soil Zn content was greater (14.37 ± 0.19 mg•kg −1 ) in a control group but lower (9.43 ± 0.32 mg•kg −1 ) in the soil of 7 DEF foriculture greenhouse.In soil samples of foriculture soil, the concentration of zinc content was recorded below the permissible limit set by CCME (<50 mg•kg −1 ).Tis work corresponds to the fndings of [46].In terms of correlation with other soil heavy metal contents, Zn was positively correlated with Ni (r � 0.28) and manganese (r � 0.05) but negatively correlated with Cr, Pb (r � −0.39), Cd (r � −0.45), and Cu (r � −0.40) (Figure 6).Te instrument working conditions for the determination of heavy metals in a soil sample by ICP-OES standard metal analysis equipment's are shown in Table 4.
Manganese (Mn) is one of the most common elements and essential metals for all living organisms within the acceptable range, but it exceeds the permissible limits and can be an important environmental and soil pollutant.Te analysis of variance revealed that foriculture Mn content was signifcantly (P < 0.05) diferent among the soils in the foriculture greenhouse.Te post-hoc test showed that foriculture soil Mn content was greater (482 ± 0.73 mg•kg −1 ) in the 5ABC greenhouse, followed by greenhouse 9DEF (467 ± 0.72 mg•kg −1 ) but lower (261 ± 0.13 mg•kg −1 ) in the control group of foriculture, as described in Table 3. Te concentration of manganese in all foriculture soil samples was above the maximum permissible limit set by CCME (64 mg/kg).Tis very high concentration of Mn might be from the repetitive use of agrochemicals (fertilizer, herbicides, and pesticides) and the soil parent materials, which are a natural source of Mn in the soil.Tis study is similar to the report of [47].
Te analysis of variance showed that foriculture Ni content was signifcantly (P < 0.05) diferent between the soils in the TAL foriculture greenhouse.Nickel (Ni) is a naturally occurring metal and essential for plant growth at low concentrations; however, Ni pollution increases in the soil environment due to the use of fertilizers, and chemicals have toxic efects on foral growth [46].
As described in the post-hoc test, foriculture soil Ni content was greater (41.50 ± 0.09 mg•kg −1 ) in the 9 DEF greenhouse, followed by the control group (38.83 ± 0.04 mg•kg −1 ) but lower (35.38 ± 0.20 mg•kg −1 ) in the 4 DEF of foriculture, as described in Table 3. Te concentration of Ni in all foriculture soil samples was below the maximum permissible limit set by CCME (100 mg•kg −1 ).A similar work was reported by [46].
Te analysis of variance showed that foriculture soil Cu content was signifcantly (P < 0.05) diferent between the soils in the foriculture greenhouse.Te post-hoc test revealed that foriculture soil Cu content was greater (102.9 ± 0.58 mg•kg −1 ) in the 9DEF greenhouse, followed by the 2ABC greenhouse (99.3 ± 0.41 mg•kg −1 ) but lower (50.8 ± 0.39 mg•kg −1 ) in the control group of foriculture soil, as described in Table 3. Te concentration of Cu in all foriculture soil samples was above the maximum permissible limit set by CCME (1.3 mg•kg −1 ).Copper (Cu) contamination of agricultural soils is a great concern due to its wide and continuous use in agriculture and horticulture as a fertilizer and fungicide [48].A similar study was reported by [42].In terms of correlation with other soil heavy metal  8 Te Scientifc World Journal contents, Cu was positively correlated to Cr (r = 0.90), Pb (r = 0.54), and cadmium (0.78) but negatively correlated with Zn (r = −0.40),as described in Figure 6.

Conclusion
Soil pollution from chemicals can afect soil health, microbiological organisms, and plant growth.Te study found signifcant variations in soil physicochemical properties and heavy metal contents between greenhouse samples from foriculture and control samples.Te soil samples had low bulk density, low pH values, low electrical conductivity, low total nitrogen, organic matter, high C/N ratios, and low available phosphorus.Heavy metal contents in the soils exceeded the permissible limit (Pb, Cd, Mn, and Cu), but Cr, Zn, and Ni contents were below.Te major limitation with this study was the reluctance of foriculture ofcials to provide soil samples as well as obtaining of laboratory equipment's and chemicals.Tis study recommends reducing agrochemical use, increasing biofertilizers, using botanicals, and transitioning into organic farming.Further studies are needed to assess soil microbial diversity and abundance for soil fxation.Te Scientifc World Journal APR MAY JUN JUL AUG SEP OCT NOV DEC Temp in °CMean annual rainfall Mean annual temperature

Figure 2 :Figure 1 :
Figure 2: Walter climate diagram of the study area (dotted areas indicate dry periods, hatched areas humid periods, and black areas wet period).

Figure 3 :
Figure 3: Correlation plot of the correlation matrix of the soil physicochemical properties.

Figure 6 :
Figure 6: Correlation plot of the correlation matrix of the soil heavy metal content of foriculture (Source: experimental data, 2022).

Table 1 :
Soil texture and BD values among greenhouse in soil foriculture (mean ± SE).

Table 3 :
Heavy metal content of soils in the study area (mean ± SE) compared with the recommended permissible limit of agricultural soil(CCME, 2007).Mean values within columns followed by the same letters are not a signifcant diference (P < 0.05), * signifcant at (P < 0.01), but diferent letters within the column have signifcant diference.

Table 4 :
Te instrument working conditions for the determination of heavy metals in a soil sample by ICP-OES standard metal analysis equipment.